GDP = [4.321 4.2352 4.2858 4.3734 4.268 4.2536 4.1162 4.276 4.3617 4.9984];
people = [43.8483 44.0982 44.5306 44.7584 45.3439 45.7628 46.3919 46.6918 47.0512 47.6006];
a = polyfit(people,GDP,1);
m = 43:0.5:48;
y = a(1)*m + a(2);
plot(people,GDP,'.',m,y,'g','LineWidth',2);
axis([43 48 4 5]);
xlabel('\bfx_{1}');
ylabel('\bfy_{1}');
title('\bfy_{1} = 0.09x_{1} - 0.37')